Variable stroke variable pressure pump or compressor



Dec. 15, 1959' J. E. SMITH 2,917,003

VARIABLE SATROKE VARIABLE PRESSURE PUMP 0R COMPRESSOR Filed April 22, 1957 1a Sheets-Sheet 1 FIGZ M, M klonwflfldiao J. E. SMITH Dec. 15, 1959 VARIABLE STROKE VARIABLE PRESSURE PUMP 0R COMPRESSOR Filed April 22, 1957 13 Sheets-Sheet 2 k 8 9. QT.

J. E. SMITH Dec. 15, .1959

VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR Filed April 22. 1957 l3 Sheets-Sheet 3 MWMJZQ J. E. SMITH Dec. 15, 1959 VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR Filed April 22, 1957 13 Sheets-Sheet 4 mxx 5 .1. E. SMITH 2,917,003

VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR R5,, 1959 .1. E. SMITH 3 1 VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR 13 Sheets-Sheet 6 Filed April 22, 1957 FIG.7

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VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR Filed April 22, 1957 J. E. SMITH l5 Sheets-Sheet '7 wt WWW 7 W W 5 CM 0 W5 7 5 i MW A Filed April 22, 1957 FIG 9 J. E. SMITH VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR l3 Sheets-Sheet 8 g fi 4 5 W i 102 is 68 /05 3 6 l 3 wk 84 25 7 I 246 M m5 94 95 /g l. v 9 /6 w r J. E. SMITH Dec. 15, 1959' VARIABLE smoxa VARIABLE PRESSURE PUMP 0R COMPRESSOR Filed April 22, 195'! l3 Sheets-Sheet 9 FIGJO x s a M 3 J M 3 l M 3 WW Y 3 VW Z/////// vv///////// %////4 z ii I M W 2 m/ U 0% K J- E. SMITH Dec. 15, 1959 VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR Filed April 22. 1957 l3 Sheets-Sheet 30 M 1 A z////vy FIGJI Dec. 15, 1959 J. E. SMITH 2,917,003

VARIABLE STROKE VARIABLE PRESSURE PUMP 0R COMPRESSOR Filed April 22, 1957 13 Sheets-Sheet l1 an I Dec. 15, 1959 J. E. SMITH 2,917,003

VARIABLE s-raoxs VARIABLE PRESSURE PUMP on COMPRESSOR Filed April 22, 1957 1a Sheets-Sheet 12 FIGJB M, w, www w Dec. 15, 1959 J. E. SMITH 2,917,003

VARIABLE STROKE VARIABLE PRESSURE PUMP OR COMPRESSOR Filed April 22, 1957 1a Sheets-Sheet 13 Flqzl 3 1 av m 7 a0 g J9 '5 77 V W W ma {56/ i I a (36% if 3; V /6 jk/ae United States Patent VARIABLE STROKE VARIABLE PRESSURE PUMP 0R COMPRESSOR James E. Smith, Houston, Tex.

Application Aprii 22, 1957, erial No. 654,182

32 Claims. (@l. 103-161) This invention relates to pumps for handling salt water, chemicals or other fluids and is more specifically directed to a pump for circulating mud or drilling fluid into an oil well while the drilling operation is being performed.

This application contains subject matter in common with my copending application, now Patent No. 2,789,515 dated April 23, 1957 and entitled, Variable Stroke Variable Pressure Pump or Compressor.

One of the principal objects of the invention is to provide a pump structure that will successfully handle abrasive fluids, fluids of different viscosities and other fluids that cause excessive wear and damage to conventional pumps.

Another object is to provide a pump which can be used with my new hydraulic drill bit shown in my copending application Serial No. 603,673 filed August 13, 1956. The present pump has a sufficient capacity and develops high enough pressures to supply drilling mud to the bit shown therein. Another object is to provide a pump whose stroke changes automatically so that the relation between the horsepower, the stroke and the pressure is always within the most eflicient or optimum range. This is important since in hydraulic drilling the pressure varies as different layers of hardness of shale, rock, etc. are reached. In conventional pumps, the pump must be stopped, torn down, and the liners replaced in order to change the pressures to obtain the optimum set of contions at the pump.

Another object is to provide novel telescoping means within each cylinder which allows the separator head to bottom or to be at the innermost or lower end of the cylinder at the end of each stroke regardless of the length of its stroke. In prior constructions, when the stroke was short and considerably less than the length of the cylinder, the end of the short stroke found the separator head in the intermediate portion of the cylinder. and not at the lower end thereof. When pumping material with much foreign matter therein, such foreign matter might possibly accumulate adjacent to the separator head under the centrifugal forces unless the separator head bottoms at each stroke.

Another object of the invention is to provide a variable stroke, variable pressure pump in which means are provided for operating the pressure producing means in a clean lubricant that is in continuous circulation and wherein impurities are scavenged by means of centrifugal or centrifuge action of the pressure producing lubricant or fluid within the pump.

Another object of the invention is to provide a continuous supply of lubricant or other working fluid for a pump and for automatic maintenance of the proper amount of lubricant or working fluid within the pressure producing cylinders.

Another object of the invention is to provide a pump for handling different kinds of fluids simultaneously and having means therein for sealing the fluids from each other while being pumped.

Another object of the invention is to provide a pump in which the inlet and outlet valves and the cylinder assemblies of the pump can be easily removed as a unit for inspection and repair.

Another object of the invention is to provide a pump in which all the valves are mounted in a single compact unit which will permit rapid exchange of one unit for another as well as providing means for removing all of the cylinders for repair and replacement, and that includes a means for sealing the valve unit or assembly when inserted in the pump by having engaging seals hydraulically operated thereby tightening and sealing the pump cylinders and valve assembly against leakage.

Another object is to utilize the discharge pressure for hydraulically maintaining the valve unit or assembly in leakproof relation with the cylinders, said pressure against the seals being greater than but in proportion to the discharge pressure.

Another object of the invention is to provide a variable pressure, variable stroke pump whose working pressure is applied to a fluid or liquid operating at high pressure against non-yielding fluid seals and at the same time pumps fluids of a nature that cannot be pumped at high pressure with pumps having yielding seals.

A further object of the invention is to provide a variable stroke, variable pressure pump having lubricating means for the several parts thereof and wherein the pressure of the lubricant supplied to the several parts varies directly with the pressure developed by the pump and applied to the parts thereof.

A further object of the invention is to provide a variable stroke, variable pressure pump in which the pump displacement is varied in accordance with the pressure produced and wherein the adjustment is uniformly applied to both ends of the pump.

Another object of the invention is to provide a multiple cylinder positive displacement reciprocating pump having no reciprocating glands therein and wherein each cylinder is provided with separator seals operating between dissimilar fluids.

Another object of the invention is to provide an improved drive and suspension for the rotating element of a radial reciprocating pump.

Another and still further object of the invention is to provide a variable stroke, variable pressure radial pump provided with means for transferring the pressure load at any stroke length to shoes which oscillate on crosshead pins and conveying the thrust load to an annular thrust ring supporting the high pressure loads Within the rotating members on anti-friction bearings and without increasing the torque loads on the driving gears and power transmitting means.

Another and still further object of the invention is to provide an improved stroke control for the pump in which the rotatable element is disposed concentrically outwardly of a removable core or valve assembly having the intake and exhaust valves mounted therein.

The invention also consists in the provision of a lubriamount or over supply of working fluid or lubricant within the cylinders provides means for releasing the excess fluid into the pumped fluid.

The invention also consists in the provision of means for an adjustment of the pump stroke to vary it in response to pressure fluctuation in the pump exhaust While simultaneously developing the necessary pressure in order .I

to continue fluid movement from the pump.

The invention further consists in the provision of a variable stroke, variable pressure pump having a body core or assembly that is forced into a registering opening in the cylinder assembly with hydraulic seal means therebetween thereby assuring tight fitting seal for the fluid seals against said cylinders.

The invention also consists in the provision of a pump having pressure producing cylinders or sleeves telescoping one within the other, the outer member of which displaces its volume into the smaller diameter of the inner member in which a separator head or fluid piston travels for separating the lubricant and fluid being pumped and wherein the separator piston travels a greater distance than the distance travelled by the outer or larger pressure sleeve and which 'diiference of travel operates lubricant intake means for maintaining an adequate volume of liquid within the cylinder.

Another object of the present invention is to provide novel means for allowing lubricant to get into and out of the cylinders.

The invention further consists in a pump capable of handling dissimilar materials without the two intermingling and wherein the discharge and inlet valves may be removed as a unit for inspection or repair leaving an opening in the pump center through which the cylinders and other parts may be removed or repaired.

The invention also consists in the provision of a pump in which the pressure applied to the lubricant for the oscillating parts thereof is equal to or slightly in excess of the discharge pressure of the pump thereby assuring a supply of lubricant in said parts.

Another object is to provide a construction wherein the projected area of contact between the crosshead pintles and the oscillating sliders is substantially equal to the projected area of the inside of the cylinder, thereby equalizing the pressure of the lubricating oil for lubricating said shoes and preventing it from being from the lubricating grooves.

The invention further consists in the provision of a pump for handling two dissimilar fluids and wherein the pressure applied to one fluid is equal to or exceeds the exhaust pressure and wherein the fluids do not intermingle but the higher pressure fluid may be released into the lower pressure fluid by reason of wear in the pump or past a safety valve.

Another object is to provide sliders mounted on the crossheads, said sliders being initially free to move completely around and within an annular groove and which find their natural position within the groove and oscillate back and forth therein without hitting any abutting surface when the pump develops pressure for pumping fluid.

These and other objects and advantages will become apparent hereinafter.

Briefly, the subject matter of the present invention includes many features which are common to those shown in my Patent No. 2,789,515. In particular, the same basic principle of pumping through a body of lubricant separated from the fluid being pumped by a separator head is employed, but the present invention contains improvements thereon. These improvements are important and represent improved pumping and wearing characteristics, simplicity of manufacture, elimination and/or reduction in problems of alignment of parts, reduction of wear, and parts which do not have to be made to as close a range of tolerance as heretofore required for proper operation.

'The important improvements contained in the present construction which are novel over the arrangement shown in my prior Patent No. 2,789,515 include but are not limited to the following items. The present construction allows the separators to bottom at all times, as shown in Fig. 9, regardless of the length of the stroke. A new method of directing oil into and out of the cylinder to obtain a variable amount of oil therein depending upon the length of stroke is provided. The trunnion pins of the prior construction have been eliminated and crosshead sliders have been provided to give greater wear and .to

prevent relatively heavy metal parts from hitting one another with resulting wear and chatter. The sliders are mounted in an annular groove and are free to find their natural position within the groove and can oscillate therein during pumping without hitting the edge of any opening therein. A new valve unit assembly is provided. This valve unit assembly contains a tapered portion at its forward end for positioning purposes and eliminates the taper previously provided at the cylinders themselves, which taper helped to seal the valve unit with respect to the cylinders. The present construction uses a novel floating cylinder seal with hydraulic means for maintaining a desired predetermined pressure against said seal. In addition, visible means are provided to detect when more lubricant or grease is needed for proper functioning of the floating seal. A novel oil collecting means is provided to collect the scavenged oil which is then filtered prior to its being returned to the main body of lubricant in the pump. The inlet valves within the valve unit assembly are operated in a different manner from that previously described which required the use of a cam to positively open and close the inlet valves. The present arrangement utilizes the pressure of the incoming fluid and the suction of the cylinders for opening the inlet valve against the action of a spring which closes said inlet valve upon completion of the suction cycle. In addition, the shaft and gear segment which operate the eccentrics for changing the stroke of the crossheads have been eliminated and replaced with suitable linkage attached directly to the hydraulic control cylinder.

The invention also consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed. In the accompanying drawings which form part of this specification and wherein like numerals and symbols refer to like parts wherever they occur:

Fig. 1 is a side elevational view of the pump and prime mover shown mounted on skids,

Fig. 2 is an end view of said pump,

Fig. 3 is a sectional view of the pump taken along the line 33 of Fig. 7 showing the position of the eccentrics when the pump is on dead center,

Fig. 4 is a sectional view taken substantially along the line 44 of Fig. 2,

Fig. 5 is a sectional view taken substantially along the line 5-5 of Fig. 1,

Fig. 6 is a sectional view taken substantially along the line 6-6 in Fig. 4, showing the position of the eccentrics at full stroke,

Fig. 7 is a side elevational view, partly in cross-section, of the pump,

Fig. 8 is an enlarged sectional view of the intake valves and hydraulic seals,

Fig. 9 is a sectional view of a piston or separator head and cylinder assembly of the pump showing a reciprocating mechanism providing for the passage of lubricant or working fluid,

Fig. 10 is a sectional view taken substantially along the line 10-10 of Fig. 9,

Fig. 11 is a sectional view similar to that shown in Fig. 10 except that the separator head is at the opposite end of its stroke,

Fig. 12 is an enlarged sectional view of the upper or crosshead portion shown in Fig. 9 except that the upper tube inlet is in registry with the crosshead inlet and the piston head on the central reciprocating tube is at the top portion of the piston chamber,

Fig. 13 is an enlarged fragmentary sectional view taken substantially along the line 13-13 in Fig. 14 showing the lubricating system in detail,

Fig. 14 is a fragmentary plan view looking downwardly on Fig. 13,

Fig. is a sectional view taken substantially along the line 1515 of Fig. 14,

Fig. 16 is a cross-sectional view taken substantially along the line 16--16 of Fig. 8,

Fig. 17 is an enlargement of the discharge valve assembly,

Fig. 18 is a cross-sectional view taken substantially along the line 18-18 of Fig. 4,

Fig. 19 is an enlarged cross-sectional view taken substantially along the line 1919 of Fig. 3,

Fig. is an enlarged cross-sectional view taken substantially along the line 20--20 of Fig. 3,

Fig. 21 is an enlarged cross-sectional view of a modified valve arrangement for directing oil into the oil chamber between the crosshead and the separator, and

Fig. 22 is an enlarged cross sectional view of another modified arrangement for allowing the necessary amount of oil or lubricant to enter the oil chamber between the crosshead and the separator.

The invention is embodied in the structure set forth in the several views of drawings in which the numeral 1 designates a set of skids on which one or two prime movers 2, preferably diesel engines, are mounted for driving the pump 3. Each of the prime movers 2 is connected to spindles 5 rotatably mounted in the housing 4 of the pump. Each spindle 5 is provided with a gear or pinion 6 meshing with an annular gear 7 circumscribing the rotatable element of the pump. The pump 3 is shown as driven by two prime movers 2 although only one may be used if so desired. A single pinion construction may be used when desired or required.

A feeder pump 8 is driven from one of the spindles 5 through gears 9 and 10. The spindles 5 constitute a part of the power transmission between the prime mover 2 and the feeder pump 8. The feeder pump 8 discharges into an inlet conduit 11 in communication with the removable core or valve assembly mechanism 12. (Fig. 4.)

The core mechanism or valve assembly 12 comprises a body or main casting 13 and a tubular extension 14 that is threaded into the main casting 13 with a seal therebetween. The body 13 has a plurality of inlet valve assemblies 15 therein for controlling the flow of material to be pumped into the pump 3. Each of these valve assemblies 15 comprises a valve seat 16 which has a flexible seal 16 on the pressure side, said seat 16 being held in leakproof contact with the valve core assembly 12 by means of a seal and being engageable by a suitable inlet valve head 17. Each valve 15 is provided with a stem 18 extending into a guide bushing 19 secured in the valve seat 16 and surrounding the valve stem 18. The valve stem 18 is provided at its inner end with a nut or enlarged portion 29. A valve spring 21 holds the intake valve 15 in closed position except during suction or intake passage of the pumped fluid into a cylinder assembly 22.

Located in the center of valve body 13 is means for hydraulically operating the fluid seals 23 which seal the respective cylinders 22 on their inner ends against leakage of the fluid being pumped. As best shown in Figs. 4 and 8, the hydraulic sealing means comprises a piston 24 having a hollow shaft 25 extending leftwardly through a gland (not shown) in the inlet conduit 11. The hollow shaft 25 is provided on its outer end with a grease fitting 26 which allows for the injection of grease through the opening in the shaft 25 into the grease chamber 27 in the body casting 13. The piston 24 is slidably mounted in the chamber 27 and is biased leftwardly by a spring 28. l

Ducts 29 connect the grease chamber 27 with the floating seals 23 which contact the lower ends of the cylinders 22. The piston 24 will produce a higher fluid pressure in the grease chamber 27 than the discharge fluid pressure in the pump cylinder 22 as well as in the discharge chamber 30 due to the shaft 25 which extends into the low pressure fluid on the intake side.

The valve core assembly 12 also contains a plurality of exhaust valves 31, which are shown in Fig. 4 with the details thereof being illustrated in Fig. 17.. These exhaust valves 31 operate as check valves and each comprises a seat 32 suitably retained within the body 13. A cooperating valve head 33 having a seal portion 33' is slidably received in a tubular bushing or guide .member 34. A spring 35 for closing the valve head 33 is located between the valve head 33 and a shoulder formed on the tubular bushing 34. The spring 35 normally holds the valve head 33 in engagement with the seat 32 and allows the exhaust valve to open in response to pressure that is applied to fluid being pumped from the cylinders into the discharge chamber 30. The plurality of valves 31 are suitably secured to a plate 36 which is secured in spaced relation to the rightward end of the body 13 as shown in Fig. 4, preferably by bolts.

To facilitate installation of the valve core assembly 12, the seals 23 are pressed down into the grooves in the casting 13. When the valve assembly 12 is locked in its proper place, grease is forced through the shaft 25 into the chamber 27 until the chamber 27 has been filled. The discharge pressure in the discharge chamber 30 acting leftwardly against the piston 24 and leftward force of the spring 28 produces pressure on the grease in the chamber 27 and forces it through the passages 29 which lead to the floating seals 23. The leftward force of the spring 28 also serves to remove the grease from the system through the shaft 25 when desired as when removing the valve core assembly 12. This is accomplished by opening a grease fitting 26 on the outer or protruding end of the hollow shaft 25. To remove the valve core assembly 12 from the supporting member 38, the pump is preferably so stopped that all separator assemblies 39 are in the central portion of the cylinders 22 so that the inlet valve heads 17 are free and clear of the separator assemblies 39. The grease fitting 26 is then opened to relieve the pressure in chamber 27 which relieves the pressure against the seals 23. The unit can then be pulled out after a locking ring 40, explained hereinafter, has been loosened.

v The housing 4 is provided at each of its two opposing sides 41 with a pair of eccentric members 42 and 43.

Each inner eccentric member 42 is provided with a securi ing portion 44 which is bolted to the side plates 41 of the housing 4 and an inner eccentric portion 45. A ring 40 with holes 46 therein is suitably drilled to match the holes 47 in the tubular extension 57 of the valve body 13, so that pins can be forced therein to force the extension to rotate With the ring 40 when installing and withdrawing the valve core assembly 12. i

The valve core assembly 12 is held in position on its inner end, or rightward portion as shown in Fig. 4, by tapered surfaces 48 in which a seal prevents leakage of fluid from a discharge chamber 30. tightening ring assembly 49 supports the Valve body 13 on its outer or leftward end with a tapered contact surface 50, and holes 51 are drilled therein to receive pins for tightening or loosening said assembly by rotating the tightening ring 49. The tightening ring 49 has an outer part 52 secured to an inner part 53 by a band 54 with a bronze ring 55 therebetween. The inner end of the inner part 53 is slotted as at 56 to permit the limited but necessary expansion of said inner end. The inner end of the extension 57 contains several axial splits as at 58 to permit the inner end to expand when the inner end of the tightening ring 49 is moved rightwardly. A bronze ring 59 is positioned between the extension 57 and body casting 13. A ring 60 is bolted to the valve body casting 13 to make contact with a shoulder on the tapered end of the inner part 53 when the valve assembly 12 is withdrawn from the pump.

The tubular extensions 14 rotate relative to a packing 61 thus providing a fluid seal on its outer end or leftward end as shown in Fig. 4. Provision is made for introducing a suitable lubricant into a packing ringholder 62 so that the lubricant and the seals will prevent leakage A centering or of the fluid which enters into the conduit or extension 14. Suitable grease seals 63 are provided between the rotating suporting member 38 and the non-rotating eccentric members 42 and the ring 40. The retaining ring 40 is suitably secured to the eccentric member 42, preferably by bolts, and said ring 40 supports the intake conduit pipe 11.

'Each side plate 41 is provided with a semi-circular portion 64 which supports the weight of the entire mechanism. In particular, the inner or center eccentric member 42 rests on and is supported by the semicircular portion 64. The eccentric portion 45 of the center eccentric member 42 has a bearing 65 around its inner circumference, said'bearing 65 comprising an outer raceway 66, a plurality of rollers 67, and an inner raceway 68 which contacts the rotating supporting member 38. The outer circumference of the inner or stationary eccentric portion 45 slidably receives the inner circumference of the outer or adjustable eccentric 43. The outer periphery 69 of the adjustable eccentric 43 forms the inner raceway of a large bearing 70 having a plurality of rollers 71 and an outer raceway 72 with a relatively thin upstanding portion 73 on which a thrust ring 74 is mounted and secured either by a pressfit or by small retaining plates 75, as best shown in Fig. 9. The thin portion 73 is provided with two ope;.ings 76 which are 180 apart for proper balance and which provide access to the parts within the thrust ring 74. The outer race 72 and the thrust ring 74 form a large internal annular groove 77 which extends 360 around the entire pump for receiving the pintles 78 which constitute the end portions of the crossheads 79, said pintles 78 having sliders 80 thereon which slide within the annular grooves 77. The sliders 80 do not normally rotate 360 within the grooves 77 but merely oscillate back and forth therein in varying amounts during the pumping operation, usually from zero to about nine or twelve degrees, depending upon the length of the stroke. In other words, the sliders 80 of adjacent crossheads 79 move toward and away from each other as the supporting member 38 rotates during pumping.

The supporting member 38 supports the ring gear 7 and is provided with a plurality of cavities 81, six in number as shown for illustration purposes, which are adapted to receive the cylinder assemblies 22 which actually receive and pump the fluid. Each cylinder assembly 22 is provided with a plurality of telescoping parts as will be explained more fully hereinafter and each cylinder is provided with a floating separating medium or mechanism 39 which seals the working fluid or lubricant from the fluid or substance which is being pumped.

One feature of the present pump is that a slightly greater pressure is maintained on the outer side than on the inner side of the separator 39. This arises by reason of the centrifugal force effective upon the separator 39', which is not positively connected to the crosshead '79. This centrifugal force tends to force the separator 39 outwardly against the lubricant in the chamber 82 outwardly thereby increasing the pressure of the lubricant in said chamber 82 relative to pressure of the fluid being pumped. The lubricant within the outer chambers 82 is purposely maintained at a higher pressure than that of the fluid being pumped on the opposite side of the separators 39 so that if and when the separating seal 83 wears and fails to seal properly, any leakage will be into the pumped fluid by reason of the greater pressure applied to the lubricant. This prevents the pumped fluid from ever entering into and contaminating the lubricant or working fluid. 7

Each separator assembly 39 comprises a seal 83 secured between a separator plate 84 and an inwardly extending flange 85 on a cylinder guide 86 by a plurality of bolts 87; A positioning ring 88 is secured in the 'lower end of the cylinder guide 86 and the separator seal 83. The positioning ring 88 is preferably made from bronze and is made to a close tolerance so that the lower end of the cylinder, guide 86 fits tightly within the cylinder liner '89. Each separator 39 is provided with a relief valve 90, as best shown in Fig. 9. The relief valve 90 may be of any suitable type but is illustrated as a passage 91 through the separator 39 which terminates in a socket 92 which receives a ball member 93 held in position by a leaf spring 94 of predetermined strength which has a hole 95 therein to receive said ball 93. The leaf spring 94 is bolted to the separator plate 84. In normal pumping operation the relief valve 90 remains closed at most times. Should an excessive amount of lubricant be supplied to the pump, that is to the chamber 82, the emergency relief valve 90 opens and discharges the excess lubricant into the discharge chamber 30. The relief valve 90 is provided to operate in the event of any failure in the hydraulically operated discharge mechanism in the chamber 82 and crosshead 79. The structure for accomplishing the aforesaid desirable pumping action will now be set forth in greater detail.

Each of the cylinder assemblies 22 which are radially disposed about and within cavities 81 in the supporting member 38 comprises a plurality of telescoping sleeves and liners and other complemental members. The supporting member 33 is provided with an integral extension 96, the bore of which receives a cylinder bearing 97, preferably made of bronze, which has a relatively large cutout portion 98 at its outer end for receiving the crosshead 79. Concentrically positioned within the cylinder bearing 97 is a cylinder sleeve 99 which extends inwardly from the crosshead 79 and is attached thereto and reciprocates therewith, there being a suitable seal 100 to prevent leakage from between the cylinder sleeve 99 which forms part of the chamber 82. An outwardly extending cylinder liner 89 is positioned within the sleeve 99., the outer end of the cylinder liner 89 being provided with a plurality of sealing rings 101 for preventing the loss of pressure and escape of fluid from within the cylinder sleeve 99 or chamber 82. It should be noted that these seals are so positioned as to be less likely to be contacted by any foreign matter in the chamber 82 which is moved outwardly by centrifugal force. Any leakage by the seals 101 will move inwardly in the space 102 having a duct 103 leading therefrom to the space between the seals 63 and drains off through the pipe 104 and back into the main body of oil which occupies a space within the lower portion of the housing 4 and is sufiiciently deep that the ring gear 7 extends into it to a desired depth. The fioating seal 23 contacts the bottom of the cylinder liner 89 Whose base portion 105 has a shoulder 106 and is held in position by a press fit within a counterbore 107 in the supporting member 38.

The mechanism which causes the telescoping sleeves and cylinder liners to move radially axially of each other is best shown in Figs. 3, 4 and 6. This comprises the pair of eccentrics 42 and 43 mounted between the supporting member 38 and the crosshead thrust members 79 on each side of the pump. As best shown in Fig. 6, the adjustable eccentrics 4-3 are rotatably mounted on the stationary eccentrics 42. By referring to Fig. 6, the degree of stroke adjustment can be ascertained. The movement of the eccentrics 42 and 4-3 relative to one another for changing the stroke of the pump in response to the exhaust or outlet pressure is substantially the same as that described in my copending application, now Patent No. 2,789,515. Thus, the stroke adjusts itself automatically in response to the fluid pressures which are required to insure proper drilling. The centers of the eccentircs 42 and 43 move toward and away from each other as the eccentrics rotate relative to each other for varying the stroke of the pump.

As best shown in Figs. 3, 6, and 7, the pump 3 is provided with. means responsive to the discharge pressure of the pump for varying the stroke. Similar means are shown in Fig. 24 of my Patent No. 2,789,515 and include a cylinder 108 with a piston 109 therein. The pump discharge pressure is effective against one side of the piston 109 through a conduit 11% and a second conduit 111 extends from the opposite end of the cylinder 108 to an air reservoir 112 partially filled with oil. The piston 109 moves in accordance with the discharge pressure and is provided with a piston rod 113 connected to a crosshead 114 having a pair of arms 115 pivotally secured thereto, said arms 115 extending to the pair of outer or adjustable eccentrics 43 for moving same. The conduit 111 between the cylinder 1118 and air reservior 112 may be provided with a valve 116 which it" closed prevents the piston 1119 from moving thereby keeping the stroke of the pump constant.

As best shown in Figs. 3, 4, 6, 7 and 18, suitable lubricating means should be provided between the two eccentrics 42 and 43. The lubricating means can be supplied by a T-connection 117 in the main lubricant inlet 118 for the pump which takes some of the main lubricant and directs it to a cylinder 119 with a plunger 120 therein operated by a cam 121 mounted on the supporting member 33 which rotates. The plunger 12% pumps lubricant upwardly through the conduit 122 which leads to a passage 123 leading to a closed groove 124 which extends between the eccentrics 42 and 43 for ap proximately 180 on the side receiving the load between the eccentrics. The purpose of the cylinder 119 and plunger 12% is to boost the pressure of the lubricant to positively force said lubricant into the grooves 124 between the eccentrics 42 and 43 to maintain an oil film therebetween even though the eccentrics are under a heavy load.

The cylinder extension 96 is preferably an integral extension of the supporting member 38 and receives and supports the cylinder bearing 97 which in turn receives and supports the entire telescoping cylinder assembly 22. The piston or separator 39 is slidably received in the cylinder liner 89 and its resilient member 83 is made from a suitable synthetic material which is not attacked by oil. One such suitable material is that sold under the trademark Neoprene by the Du Pont Co. The separator seal 83 and plate 84 have a central opening 125 for receiving the inner end of a reciprocating plug 126, the function of which will be described later in greater detail.

The supporting member 38 at its outer perimeter has the large gear 7 attached thereto meshing with the gears or pinions 6 on the spindles which impart rotational movement to the pump assemblies within the appropriate openings which are radially positioned about the bearing 65. Stated differently, the housing 4 supports the stationary eccentrics 42 which in turn support the bearings 65 within which the rotating parts attached to the supporting member 38 rotate.

The pump is lubricated from a suitable source of lubricant delivered thereto under pressure and introduced into a port 127 out in the exhaust thrust casting 128. This casting 128 is non-rotatable and is supported on the member 38 by a thrust roller bearing 129 and a bronze bearing. Lubricant is introduced into the port and is then conducted through ports formed in the bronze bearing 130 into passages 131 in the member 38 emerging through the pipes 132 into the chamber 133 formed in rocker assembly 134, which provides fluid connection to the drilled holes 135 and 136 in the crossheads 79. This provides the necessary lubricant connections from the non-rotating portion of the structure just described to the rotating structure and to each of the pump cylinders. Each rocker assembly 134 has an inner slide 137 and an outer slide 138. The inner slide 137 has a pivot 139 mounted Within the crosshead 79. The outer slide 133 has a pivot 140 mounted within a block 141 secured to the supporting member 38. An opening 142 in the rocker assembly 134 forms a movable connection between the pipe 132 and the drilled hole 135. If desired, each rocker assembly 134 may be replaced with a flexible hose.

The centrifugal force exerted on the mass of the separator assembly 39 tends to return the separator 39 to its retracted or outer position, as shown in Fig. 11, after each discharge or radially inward movement of the cylinder sleeve 99. The centrifugal action produces a greater pressure on the lubricant in the chamber 82 than the pressure of the pumped fluid on the opposite side of separator assembly 39 as hereinbefore mentioned.

From the foregoing it is apparent that a variable stroke, variable pressure pump including suitable crosshead bearing sliders 3% has been provided, and also, a source of lubrication within the pressure producing cylinders for lubricating said bearing sliders has been provided, said lubricant flowing through enclosed grooving or ducts at a pressure that varies in direct proportion to the load imposed on the thrust receiving members. The mechanism provides a means for the lubricant to be taken from the radially inward portion of the lubricant chamber 82 through the tubes 143 (see Fig. 11) where it is free of foreign matter by reason of the centrifugal action on the rotating cylinders. Preferably, the ends 144 of the tubes 143 are free and clear of, but are in close proximity to the separators 39 so that relatively clean lubricant moves through the tubes 143. The tubes 143 are in communication with ducts 145 formed in the crossheads 79 terminating in the bearing sliders 80 mounted on the pintles 78. The ducts 145 lead to the passages 146 which lead to the grooves 147 in the sliders 80.

In operation, the prime movers 2 drive the pump 3 through the large gear 7 which causes the supporting member 38 to rotate. The thrust ring 74 which supports the crossheads 79 rotates with the supporting member 38 but on a different center so that as the two members rotate, the crossheads 79 move radially inwardly and outwardly with respect to the supporting member 38. This movement of the crossheads 79 initiates movement of the separators 39 through the lubricant within the chamber 82 which remains constant at constant stroke operation except for that which is pumped for lubrication purposes and for scavanging. Thus, the force required for the pumping action is transmitted to the separators 39 through the lubricant in the chamber 82. The central telescoping assembly 148 merely controls the supply of oil to and from the chamber 82 and maintains the correct amount therein.

It is to be noted that there is no positive connection between the thrust ring 74 and the supporting member 38 so that when the pump 3 starts up the thrust ring 74 might slip in a harmless manner with regard to the supporting member 38 until pressure has been built up at which time the sliders 80 on the crossheads 79 are forced into such tight relation with the thrust ring 74 that the two rotate together. When fluid is being pumped, all of the sliders 80 are forced against the top or the bottom of the groove 77 in the thrust ring 74. However, the great friction between the sliders of those cylinders which are in compression and the thrust ring 74 keep the ring 74 and the supporting member 33 rotating together, although there is some assistance from the sliders on those crossheads in the cylinders which are in suction due to the centrifugal force.

During the suction stroke, the inlet valve 15 is opened and the fluid enters the cylinder liner 89 because of the suction created during the outward movement of the separators 39 in the cylinders. The force of the incoming pumped fluid against the valve head 17 overcomes the force of and compresses the spring 21, thereby moving the head 17 outwardly. At the completion of the suction stroke, the valve 15 is closed since the incoming flow against the head 17 is stopped, thereby allowing the spring 21 to move the head 17 against its seat 16. The compression cylinder sleeve 99 and the crosshead 79 then begins its compression stroke forcing the oil in the chamber 82 into driving relation with the cylinder guide 86 moving same into telescoping relation to the cylinder liner 89 *thereby -positively moving the separator 39 against thepumped fiuid'and out of the cylinder liner 89 past the exhaust or check valve 31 into the exhaust chamber 30 of the pump 3.

In the event that the travel of the separator 39 is excessive by reason of an over supply of lubricant within the chamber 82 which might occur by failure of the hydraulic feeder system, the relief valve 915 in the separator-39 will open and release the excess lubricant through the passage 91 to the fluid being pumped. Fig. shows the position of the separator cylinder sleeves and the lubricant tube parts at various stages during the compression and suction strokes when the pump is in full stroke operation.

The lubricant that is supplied to the sliders iii? by reason'of the pressure in the chamber 82 will be in direct proportion to the thrust load on the crosshead 79. The projected area of the bearing surfaces of the sliders 80 and the projected area of the inside of the cylinder sleeve 99 are approximately the same. Consequently, the lubricant that is forced through the conduits 143, 145, and 146 and into the closed grooving 147 in the sliders 79 will be at approximately the same pressure as is pres out within the chamber 82. This balance will prevent a squeezing of lubricant from the grooving 147 illustrated in Fig. 14 and will at all times provide a flow of lubricant under the same varying pressure as the thrust load varies against the pintles 78.

The drilled hole or passage 135 provides a connection for the passage of lubricant into the crosshead center and into the opening-136 which is in the crosshead 79 as best shown in Figs. 9, 11, 12, and 14.

The purpose of the rocker assembly 134, one end of which operates in the crosshead 79, and the central telescoping assembly 143 which operates in the chamber 82 is to provide means for automatic intake and outlet of lubricant in the chamber 552. The assembly 148 comprises a tube or plunger 149 which has on its outer end a spring 159 suitably retained between an outer cap 151 and a shoulder 152. The plunger 149 is shown in two parts, the upper part 153 being threaded into the piston end 154- of the lower part 155. The upper portion 153 of the plunger 149 reciprocates in a sleeve 156 which is held in place by nut 157. The sleeve 156 contains an intake port 158 which connects with an intake hole 136 in the crosshead 79 and outlet ports 159 and passage 160 in the crosshead '79 which connects with the outlet hole 161 in the crosshead 79. A series of ports 162 with an annular passage 163 leading therefrom connects with the outlet port 159 to permit the excess oil in the chamber 32 to escape therefrom. The inner end of the sleeve 156 contains a chamber 164 which receives the piston end 154 of the plunger 149. The ports 162 provide an opening for the escape of lubricant from the chamber 82. During each suction stroke a small amount of oil enters the chamber 82 and the assembly 1 38 provides for its inlet and outlet. The oil enters when the opening 170 in the plunger 149 registers with the holes 136, as shown in Fig. 12, and the oil leaves when the port 162 is open as shown in Fig. 9. The port 162 automatically closes by reason of the spring 1511 when the pressure in the chamber 167 is released when the plug 126 moves inwardly or downwardly at which time the suction begins.

The central assembly 148 is connected to the separator 39 and has a plunger guide 165 secured to the flange 85 of the cylinder guide 86. The inner portion 01 the guide 165 slid-ably receives plunger 149. The plug 126 has an outer enlarged portion 166 slidably mounted in the inner end of the guide 165 forming a chamber 167 in intermittent communication with holes 168 in the guide 165. A spring 169 is positioned within the plug.126 and biases said plug inwardly.

The assembly 148 operates in a manner to provide for the intake and outlet of lubricant into the chamber 12 82, and also to provide means whereby the separator 39 will completely discharge all of the fluid being pumped within its cylinder at each discharge stroke caused by movement of the crossheads 79, regardless of the length of said discharge stroke.

In other words, the separator head 39 will always go to the bottom position, as shown in Fig. 9, that is, to the inner end of cylinder 89 at each reciprocation. During the suction cycle of the pump as viewed in Figs. 11 and 12, the intake port 158 is in registry with the transverse opening 176 in the upper portion 153 of the plunger 149, permitting lubricant to flow through the plunger 149 into the chamber 167 and then through the orifices 168 in the member 165 into the chamber 82. When the plunger 149 is in this position, the discharge ports 162 are closed. The upper portion 153 of the plunger 149 is provided with a shoulder or seat 171 to make certain that the discharge ports 162 are closed at times and that the wearing of the parts does not result in leakage through the port 162 to the annular passage 163 and out through the outlet port 159, as shown in .ig. 9.

A small amount of lubricant will continue to flow as pointed out above during the suction stroke into the chamber 82 and will continue its flow until the separator head 39 reaches its bottom position, shown in Fig.9, at which time the bottom end of the plug 126 will contact the top of the intake valve 17. The plug 126 will then be forced upwardly closing the ports 168 and will produce a hydraulic pressure in the chamber 167. This pressure will be transmitted to the chamber 164 through the central passage 172 in the plunger 149 and thence through transverse holes 173. This pressure is retained in the chambers 164 and 167 by reason of the ball or check valve 174 which prevents the outward or reverse flow of lubricant. This hydraulic pressure in the chamber 164 will act against the piston portion 154 of the plunger 149 and will cause the movement of the plunger 149 to its bottom position, as shown in Fig. 9, in which position the discharge ports 162 will be open, through which all excess oil will escape to the annular passage 163. Through this means the volume of oil in the chamber 82 will vary as the pump stroke varies by reason of the fact that no oil will be bled out of the chamber $2 until the plug 126 has compressed the fluid as'hereinbefore described. If desired, a metering valve could be installed in the crosshead 79 or some other suitable point between the chamber 32 and the source of supply to reduce or increase the flow of oil to the chamber 82.

Since the ports 162 are located at the outer end of the chamber 32, the centrifugal force caused by the rotation of the pump will cause any foreign matter that may be present in the lubricant in the chamber 82 to pass through ports 162 into the annular spacer 163 to the drilled hole in the crosshead '79.

Further explaining the operation of'the telescoping sleeves and members within the chamber 82, as the crosshead 79 moves outwardly, the cylinder sleeve 99 attached to the crosshead 79 moves outwardly. This relieves pressure within the chamber 82 and the plug 126 in the separator head 39 moves outwardly and away from the top of the intake valve 17 at which time pressure is relieved on the oil within the chamber 167 and in the chamber 164 which allows the plunger 149 to move upwardly by action of the top coil spring 150 and centrifugal force as far as possible to allow the transverse opening 179 to align itself with the'oil inlet port 158 at which time the plug 126 in the separator head 39 due to the spring 169 therein moves downwardly in the chamber 167 and creates a suction in the chamber 167 to allow oil from the intake port 158 in the'crosshead 79 to be sucked into the chamber 167 until the ports:168 in the plunger guide are uncovered to allow the passage of lubricant into the chamber 82. The chamber 167 has pressure thereinuntil the plug 126 starts mov'e- 13 ment within the chamber 167. Then the spring 169 moves the plug 126 in the chamber 167 and creates a suction in the chamber 167 and allows the upper spring 150 to move the plunger 149 upwardly with the help of centrifugal force until the cross passage 170 aligns itself with the crosshead intake port 158. When the ports 170 and 158 register, the lower plug 126 moves downwardly in chamber 167 thereby sucking in oil until the ports 168 are opened in the guide 165. At this point, the intake oil can enter the chamber 82 and the spring 169 pushes the lower plug 126 downwardly.

Fitted into the crosshead 79 into the hole 161 is a pipe 175 leading into an open sided tube 176 attached to the member 38, as shown in Figs. 3, 9, 12, 14, and 19. The tubes 176 terminate on their outer ends into an open sided tube 177 which is mounted circumferentially on the side of the gear 7, as shown in Figs. 3, 4, 6, 14, 19 and 20. The lubricant from the chamber 82 that is dis charged through the ports 162 will flow as above stated, into the circumferential tube 177, where the centrifugal force will cause the heavier matter present in the lubricant to accumulate in the outer perimeter of the open sided tube 177. Through the opening in the side of tube 177 as best shown in Figs. 3, l9 and 20, is a pipe 178 whose end is shaped and fitted to act as a scoop, since the tube 177 rotates with the gear 7 and the pipe 178 does not rotate but leads to the outside of the pump. The pipe 178 with its scoop like end will provide means for the passage of the lubricant to a suitable filter or centrifuge outside the pump housing, and will prohibit the main body of lubricant within the pump from becoming contaminated with any foreign matter discharged from the chamber 82. The pipe 178 and the ring gear 7, as well as most of the other parts described, are within acover 179 which is suitably secured to and forms part of the housing 4.

One of the essential advantages of the pump described is that the valve core assembly mechanism 12 which contains the intake and exhaust valves can be quickly disassembled from the machine and the cylinder liner 89 and other parts therein may be quickly replaced without the necessity of completely dismantling the pump. This greatly reduces the out of service time of the pump and the core assembly materially reduces the time required for assembling the same into the pump housing thereby placing the pump back in service in a shorter length of time than can be done in comparable mechanisms known to the art. Other advantages have been outlined previously during the description of the construction and operation of the pump.

Fig. 21 shows an enlarged cross-sectional view of a modified valve arrangement for directing oil into the chamber 82. The operation of the pump and each cylinder therein is substantially the same as hereinbefore described except for the manner in which the oil is directed into the chamber 82. In the modified form, the crosshead 79 is provided with a drilled hole 136 which terminates short of the sleeve 156. A needle valve 180 with a lock nut 181 thereon is positioned in the crosshead 79 to control the flow of oil through the passage 136 which is provided with a vertical portion 136a which leads to a small plug 182 having a check valve 183 therein. The check valve 183 permits oil to flow into the chamber 82 but prevents oil from escaping from said chamber through the passage 136a. In this modified form, the sleeve 156 is modified in its lower portion and is provided with a conical seat 171a adapted to cooperate with the conical portion 184 on the lower end of the upper portion 153 of the central telescoping assembly 148. If desired, the upper portion 153 may be provided with a vertical hole and cap member (not shown) for removing any foreign materal that might happen to accumulate within the chamber 164.

Fig. 22 shows a cross-sectional view of a modified arrangement for allowing the necessary amount of oil to enter the chamber 82 when required. This modified form is especially adapted for use with pumping relatively pure materials, such as oil through pipe lines. It further constitutes an improvement over the telescoping arrangement shown in my Patent 'No. 2,789,515. Unlike the arrangement shown in Fig. 9 herein, this modified arrangement shown in Fig. 22 does not cause the separator 83 to bottom on each stroke when the pump is not operating in full stroke position. The modified form as shown comprises a tubular extension 185 which extends inwardly from the crosshead 79. Within the extension 185 are mounted an outer check valve housing and seat 186 with a ball 187 therein, a

check valve housing 188 with a ball 189 therein, a spring 190, and a retainer 191 threaded or otherwise retained within the extension 185. The check valve housing 188 supports a ball housing 192 having a relatively large ball 193 normally biased against a hole 194 in the bottom of the housing 192 by a spring 195. The flange 85 on the cylinder guide 86 is provided with an outwardly extending projection 195 in registering relation with the hole 194.

In operation, the ball 193 remains in its closed position until such time as oil is required in the chamber 82 at which time the cylinder guide 86 moves outwardly so that the projection 195 unseats the ball 193 thereby allowing oil to enter the chamber 82 from the passage 136 through the check valves 187, 189, and 193. When sufiicient oil is Within the chamber 82, the cylinder guide 86 cannot move upwardly or outwardly sufiiciently far to cause the projection 195 to unseat the ball 193. The check valves 187 and 189 prevent the passage of oil from the chamber 82 to the passage 1.36. With this type of an oil inlet arrangement, a suitable valve or metering device such as that described and shown in Fig. 23 of my Patent No. 2,789,515 may be provided in cooperative relation with the chamber 82 for the purpose of removing foreign matter that may accumulate in the chamber 82.

This invention is intended to cover all changes and modifications of the examples of the invention herein chosen for purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.

What I claim is:

1. A pump comprising a plurality of angularly arranged cylinders, said cylinders each having a plurality of telescoping sleeves therein, a separator in each of said cylinders, means for rotating said angularly arranged cylinders, an intake and exhaust valve operatively asso 'ciated with each of said cylinders, means for varying the stroke of said separators relative to said cylinders, and means within said cylinders for causing said separators to have the same bottom position within the cylinder on each stroke.

2. A variable stroke pump comprising a plurality of angularly arranged cylinders, said cylinders each having a plurality of telescoping sleeves therein, a separator in each of said cylinders, means for rotating said angularly arranged cylinders, an intake and exhaust valve assembly positioned along the axis of rotation of said cylinders, means responsive to the discharge pressure of the pump for varying the stroke of said separators relative to said cylinders, and means within said cylinders on the opposite sides of said separators from said valve assembly for causing said separators to have the same bottom position within the cylinder adjacent to said valve assembly on each stroke regardless of the length of the stroke of said separators.

3. A pump comprising a rotatable supporting member, a plurality of angularly arranged cylinders, each cylinder having a plurality of telescoping sleeves therein, one of said sleeves in each cylinder being operatively associated with a crosshead, a reciprocating separator in each of said cylinders .m movable relation with said crosshead, 

